Get energised for some natural winter warmth

BRIGHT IDEA: We increased solar gain by adding glazing to the northern sides of our villa.

Although I was unaware of it at the time, my first birthday coincided with a significant number one hit by The 5th Dimension on the US Billboard Pop Singles Chart.

Here is a music trivia quiz:

The song is a medley of two songs.

It was the first medley to top the American charts.

It remained at number one for six weeks in April and May, 1969.

It reached number one in Canada and number three in Australia.

It was replaced at number one in the US by Get Back by The Beatles.

It featured prominently in the musical Hair.

Whanganui's aging hippies will easily recognise this song as Aquarius/Let the Sunshine In.

One of my earliest childhood memories was going to a high school production of Hair and absolutely loving it. Afterwards, my brother and I dug out my parents' LP and listened to it over and over again.

To this day, we both remain avid music listeners while retaining complete lack of talent.

So what is my point in all of this? Two points: 1) you do not have to be proficient at something to appreciate it deeply; 2) let the sunshine in.

Whether or not this is the Age of Aquarius, I reckon it certainly is the age of designing homes to take advantage of free and abundant sunlight energy.

One need not be proficient in eco-design to appreciate this. One need simply pay a power bill and wish it were lower.

The basics of passive solar home design date back hundreds or even thousands of years in some cultures, but the modern era of passive solar dates to about the time when The 5th Dimension was at the peak of their popularity.

Passive solar design consists of solar gain, thermal mass and insulation.

During our renovation we increased solar gain by adding glazing (windows and French doors) to the northern sides of our villa.

At the same time we removed glazing from the southern sides.

If we think of a home as a bank account for energy: in winter, the north facing windows make deposits during the day and withdrawals at night, while the south facing windows make withdrawals day and night (unless we happen to get an unseasonably warm day).

In the end, we had roughly the same amount of total glazing in our home but it was more appropriately placed to take advantage of solar gain and minimise heat loss.

Our renovated villa has performed admirably of late. Up until this week we have not had to use any heat source aside from the sun. Operating only on solar energy, our indoor temperature remained over 17C right up until the early morning of Mother's Day.

From April 28 to May 3 when the outdoor high each day was 15 or 16C, our indoor temperature never dropped below 18C. Nelson Lebo consults businesses, schools, and home-owners on all aspects of sustainability - email: theecoschool@gmail.com or phone 06 3445013 or 022 6350868.